Radio tuning apparatus



March 10, 1936. R GUEST 2,033,825

RADIO TUNING APPARATUS Filed July 25, 1955 2 Sheets-Sheet l a" I 2 I9 /6g /7 F E E i I E /2 g Inventor A Home];

March 10, 1936. GUEST 2,033,825

RADIO TUNING APPARATUS Filed July 25, 1935 2 Sheets-Sheet 2 l6; gm /6 Eg 2 i E 5 E l2 3 7 E13 6 E M g Invenlor Patented Mar. 10, 1936 PATENTOFFICE RADIO TUNING APPARATUS Herbert Rainford Guest, Habana, CubaApplication July 25, 1935, SerialNo. 33,168

3 Claims.

The present invention relates to new and useful improvements in anapparatus for use particularly in tuning radio receiving sets but itwill be understood, of course, that the invention may be used for anypurpose for which it may be found adapted and desirable.

The primary object of the invention is to provide, in manner ashereinafter set forth, an apparatus of the aforementioned characterembodying a novel construction, combination and arrangement of partsthrough the medium of which coarse and fine adjustments may beexpeditiously made.

Other-objects of the invention are to provide an apparatus of thecharacter described which will be comparatively simple in construction,strong, durable, highly efficient and reliable in operation, compact andwhich may be manufactured at low cost.

All of the foregoing and still further objects and advantages of theinvention will become apparent from a study of the followingspecification, taken in connection with the accompanying drawingswherein like characters of reference designate corresponding partsthroughout the several views, and wherein:--

Figure 1 is a view in side elevation, showing the apparatus in positionfor making coarse adjustments.

Figure 2 is a side 'elevational view, showing the apparatus in positionfor making fine adjustments.

Referring now to the drawings in detail, it will be seen that theembodiment of the invention which has been illustrated comprises a shaftI which extends rotatably and slidably through the panel 2 of thecabinet of a radio receiving set. The inner end portion of the shaft Iis supported in a bearing 3 on the free end of a bracket 4 which isrigidly secured to the inner side of the panel 2, as at 5. Fixed on theouter end portion of the shaft I is an operating knob 6.

Also fixed on the shaft I, at longitudinally spaced points between thebracket 4 and the panel 2, are gears I and 8, the latter being ofsmaller diameter but wider than the former. A coil spring 9 encirclesthe shaft I between the bearing 3 and the gear 8 and yieldingly urgessaid shaft outwardly. Washers III are provided between the coil spring 9and the bearing 3 and between said coil spring and the gear 8.

Washers II and I2, through which the shaft I passes, are provided on theinner and outer sides of the panel 2. As will be apparent, the washersII and I2 constitute bearings for the shaft I.

Fixed on the shaft I; between the gear I and the panel 2, is a collar13; A collar I4 is also fixed on the shaft I between the panel 2 and theknob 6. It may be well to here state that the collars I3 and I4 areengageable with the washers II and I2, respectively, in a manner tolimit the sliding movement of the shaft I. Mounted on the inner side ofthe panel 2 is a comparatively strong spring I which is engageable withthe collar I3 for releasably securing the shaft I in the position shownin Figure 1 of the drawings against the tension of the coil spring 9.

The reference numeral I6 designates a rotary shaft which is mountedabove the shaft I in parallelism therewith, one end of said shaft I6 be-15 ing journaled in a suitable bearing H which is provided therefor onthe inner side of the panel 2. The other end portion of the shaft I6 isoperatively connected to the usual variable condenser, etc., of theradio receiving set. Fixed at spaced points on the shaft I6 are gears I6and I9, the latter being smaller in diameter, but wider, than theformer.

The gear I is adapted to engage the gear I9 for driving the shaft I6 atcomparatively high speed, as illustrated to advantage in Figure 1 of thedrawings, and the gear 6 is adapted to engage the gear I8 (see Figure 2)for driving said shaft I6 at comparatively low speed. When a coarse butrapid adjustment is desired, the shaft I is pushed inwardly to engagethe gear I with the gear I9 and disengage the gear 8 from the gear I8,the collar I3 passing the free end of the spring I5. Inward movement ofthe shaft I is arrested by the outer collar I4. The shaft I is thenrotated through the medium of the knob 6 to drive the shaft I6. Thespring I5 is sufficiently strong to hold the shaft I in its innerposition against the tension of the coil spring 9. When a fineadjustment is desired, the shaft I is pulled outwardly with sufiicientforce to move the collar I3 past the spring I5 and engage the gear 8with the gear I9. The shaft I is yieldingly secured in its outerposition, as in Figure2, by the spring 9. Outward movement of the shaftI is positively limited by the engagement of the collar I3 with thewasher II. When the gear I is operatively engaged with the gear I9, thegear 8 is disengaged from the gear I8, and vice versa. However, owing tothe width or length of the gears 8 and I9, the gear I8 is not releasedfrom the gear 8 until after the gear I is engaged with said gear I9 andvice versa.

It is believed that the many advantages of an apparatus constructed inaccordance with the present invention will be readily understood, and 5although a preferred embodiment of the device is as illustrated anddescribed, it is to be understood that changes in the details ofconstruction and in the combination and arrangement of parts may beresorted to which will fall within the scope of the invention asclaimed.

What is claimed is:-

1. An apparatus of the class described comprising a rotatably andslidabLv mounted drive shaft, a driven shaft rotatably mounted inparallelism with said drive shaft, comparatively large and small gearsfixed on the driven shaft, 8. gear fixed on the drive shaft andoperatively engageable with the small gear, a comparatively small gearfixed on the drive shaft and operatively engageable with the larger ofthe first-named gears, a spring yieldingly urging the fourthnamed geartoward operative position, a collar fixed on the drive shaft, acomparatively strong spring releasably engageable with said collar forsecuring the third-named gear in operative position, and means forrotating the drive shaft.

2. An apparatus of the class described comprising a drive shaftrotatably and slidably mounted in a support, collars fixed on said driveshaft on opposite sides of the support and engageable therewith forlimiting the sliding movement of said drive shaft, a driven shaft, agear fixed on said driven shaft, a comparatively small gear fixedon saiddriven shaft, a gear fixed on the drive shaft, another gear fixed onsaid drive shaft, the fourth-named gear being of greater diameter thanthe third-named gear, said thirdnamed gear being operatively engageablewith the first-named gear when the fourth-named gear is in inoperativeposition and said fourthnamed gear being operatively engageable with thesecond-named gear when the third-named gear is in inoperative position,the second and third-named gears being comparatively wide, a coil springencircling the drive shaft and engaged with the third-named gear foryieldingly urging the same toward operative position, a comparativelystrong spring engageable with one of the collars for releasably securingthe fourth-named gear in operative position against the tension of thefirst-named spring, and means for actuating the drive shaft.

3. An apparatus of the class described comprising a driven shaft, gearsfixed on said driven shaft, a support, a drive shaft rotatably andslidably mounted in said support, collars fixed on said drive shaft forlimiting the sliding movement thereof in opposite directions, gearsfixed on said drive shaft, one of the second-named gears beingoperatively engageable with one of the firstnamed gears, the other ofthe second-named gears being operatively engageable with the other ofthe first-named gears, a spring operatively connected to the drive shaftfor yieldingly urging said one second-named gear toward engagedposition, a comparatively strong spring mounted on the support andreleasably engageable with one of the collars for releasably securingsaid other of the second-named gears in operative position against thetension of the first-named spring, and means for actuating the driveshaft.

HERBERT RAINFORD GUEST.

